P917: HOW COMORBID ARE OUR MYELOMA PATIENTS AND HOW MANY MAKE IT TO THE SECOND-LINE TREATMENT: REAL-WORLD DATA OF 251 MYELOMA PATIENTS TREATED IN THE HEMATOLOGICAL NETWORK OF THE OEGK
Authors: F. Keil, P. Attalla
Journal: HemaSphere (2022)

Background: Comorbid conditions have a negative impact on overall survival (OS) in multiple myeloma (MM) patients. Furthermore, a European multi-center study reported that only 61% of patients proceed to second-line treatment. Aims: The objective of this study was to determine the prevalence of common comorbidities and their impact on OS. Furthermore, we examined the mortality during first-line treatment and the percentage of patients proceeding to second-line treatment. Methods: This retrospective study was conducted in the hematology care network “Hämatologieverbund der Österreichischen Gesundheitskasse (OEGK)”, consisting of the Hanusch hospital and three outpatient centers, in Vienna, Austria. We included all patients who were observed and/or treated for multiple myeloma between 2012 and 2018 within the hematology care network. Follow-up was conducted until March 2021. Results: We analyzed 251 patients (median age 69 years). Prevalent concomitant conditions at diagnosis were hypertension (67.4%), further cardiovascular diseases excluding hypertension (23.1%), obesity (15.2%), diabetes (13.8%) and chronic lung disease (9.2%). For the evaluation of renal impairment, we used the CCI, which defines kidney disease as a creatinine >3mg/dl or the need for dialysis, as well as the chronic kidney disease (CKD) classification system. While 7.8% of patients fulfilled the CCI criteria for kidney disease, 39.5% had a CKD stage ≥3A. Comorbidity in general, as well as specific comorbid conditions had a negative effect on overall survival. Patients with a CCI score of 0 points at diagnosis showed a median OS of 8.7 years compared to 3.8 years and 2.6 years for patients with a score of 1 point and ≥2 points, respectively (p <0.001). We also observed a reduced OS of 4.9 years in patients with at least one creatinine clearance (CrCl) value <60 ml/min throughout the observation period compared to 16.4 years in patients with a CrCl consistently ≥60 ml/min (p <0.001). In total, 232 patients received a first-line treatment. During the observation period after first-line therapy, 146 patients proceeded to second-line treatment due to progress, 30 showed no sign of progress so far and 12 had an ongoing first-line maintenance therapy. 21 patients were referred from other centers for a second opinion and/or ASCT. These patients were still alive at the end of the observation period, but data about further treatment lines were missing. One patient eligible for second-line treatment refused further therapeutic measures. Furthermore, 22 patients died during first-line treatment or the subsequent treatment-free interval. Of these 22 patients, 11 died during active first-line treatment due to progression of myeloma or treatment-related toxicity. The other 11 patients died after completion of first-line treatment during the observation period due to secondary neoplasms (4) and infection (2). For the remaining five patients the cause of death was unknown. In total, 90.5% of patients who had received a first-line treatment were or still are eligible for second-line treatment. Summary/Conclusion: Comorbid conditions were prevalent in our population and exerted a major impact on mortality. In comparison to the CCI, the chronic kidney disease classification system showed superior sensitivity for detection of renal impairment, which is a good predictor of survival. In contrast to previously published data, a high proportion of patients were eligible for second-line treatment. Disease-specific mortality prevented only a small number of patients from receiving second-line treatment.